Dial mechanism for radio apparatus



Jain; 1 7; 1928. 1,656,532

W. A. READY v DIAL MECHANISM FOR RADIO APPARATUS Filed June 9 6 1771267 @607 LUZJLYILQJVZ Ji Qeady.

E'Patented Jan. 17, 1928.

UNITED STATES PATENT OFFICE.

WILLIAM A. READY, OF BROOKLINE, MASSACHUSETTS.

DIAL MECHANISM FOR RADIO APPARATUS.

Application filed June 11, 1926. Serial. No. 115,407.

March 16, 1926, which application contains 10 generic claims.

The invention consists in the combination and arrangement of parts set forth in the following specification and particularly as pointed out inthe claims thereof.

15 Referring to the drawings 2- Figure 1 represents a side elevation of a variable condenser for a radio apparatus, the dial mechanism embodying my invention being operatively connected thereto and 20 illustrated partly in section and partly in elevation.

Fig. 2 is a front elevation of the mechanism as viewed from the right of Figure 1, the operating knob being removed from the 25 driving member.

Fig. 3 is an enlarged central vertical section through the driving member and a portion of the driven member, the former engaging the latter to drive the same at its 30 maximum ratio of angular displacement.

Fig. 4 is a detail sectional elevation .:is taken on the line 4-4 of Fig. p

Fig. 5 is an enlarged detail section illustrating the relative positions of the driving anddriven members, when the former is positioned to drive the latter at its minimum ratio of angular displacement. 4

Like numerals refer to like parts through. out the several views of the drawings.

In the drawings. 5 represents a variable condenser of well-known formythe same being-mounted in any suitable manner upon a panel 6. The condenser 5 embodies therein a frame 7 upon which a plurality of rotor 45 plates 8 are mounted in any suitable manner upon a rotor or dial shaft 9, the latter being journalled in said frame 7. Also mounted upon the frame 7 are a plurality of stator plates 10, the latter being mounted in anysuitable manner upon posts 11 and 12. which, in turn, are mounted in insulating blocks 13 and 14 respectively, fastened to' said frame.

In order that a very delicate adjustment may be obtained between the rotor and stator plates, a dial mechanism is provided for the condenser 5 and it is'in this dial mechanism that the novel features of this invention reside. Mounted upon the outer extremity of the rotor shaft 9, upon the opposite sides of the panel 6 from that upon which the condenser 5 is mounted, is an auxiliary panel 15 and all of the parts of the dial mechanism are mounted upon said auxiliary panel and so assembled as to constitute a selfcontained unit, which may be attached to or removed from the dial shaft in its entirety at any time without disturbing any of the various parts thereof.

Mounted upon the exterior of the auxiliary panel 15 is a bushing 16 having a shouldered portion 17 formed thereon which projects through said auxiliary panel, and rigidly fastened to said shouldered portion 17 and located within a recess 18 at the rear of saidpanel is a driven member 19, the

latter embodying therein a friction disc 20 and a circular friction spring 21, said disc and spring being securely fastened together by a plurality of rivets 22. The bushing. 16, in effect, forms a hub for the friction disc 20 and is rigidly secured to the dial shaft 1 9 by a screw 23.

The friction disc 20 has a beveled surface 24 provided thereon which engages with a similarly beveled surface 25 of a driving member 26 hereinafter to bemore fully described, and the friction spring 21 has a resilient portion 27 and the latter is curved at'28 adjacent to the periphery thereof and said curved portion engages a beveled surface 29 of the driving member 26. The disc 20 and friction spring 21 are so formed as to provide a space 30 therebetween', and the driving member 26 projects into this space and is engaged upon its opposite sides by the beveled surface 24 of the disc 20 and the curved surface 28 of the spring 21, said spring and disc pinching the driving member therebetween.

The front face of the disc 20 is provided with a shallow recess 31, in which an indicator 32 of sheet material is rigidly secured in any suitable manner, the front face of said indicator being flush with the front surface of said ,disc. ,The indicator 32 is provided with a plurality of graduations 33 and reference characters 34 which are visible through an opening 35 provided in the auxiliary .panel. 15. A thin transparent member 36 is secured to the rear of the auxiliary panel 15 and extends across the opening 35, and saidtransparent member as an opening 37 formed therein, thereby enabling the operator of the radio apparatus to mark the designations of the different radio stations upon the surface of the indiester 32 at points opposite the graduations 33.

The drivin member 26, previously mentioned, is pre erably formed integral with a spindle or shaft 38 which constitutes a vernier shaft, and the latter is rotatably mounted within a bearing member 39, which in turn is rotatable within the auxiliary panel 15. The Vernier shaft 38 is so positioned within the bearing member 39 that the axis of said vernier shaft is eccentric to the axis of said bearing member. The bearing member 39 has a resilient operating arm 40 rigidly fastened thereto, at the outer extremity of which is a pin 41 which is adapted to spring into any one of a plurality of shallow recesses 42 provided in the auxiliary panel 15 and arranged concentric with the axis of the bearing member 39. The spring tension upon the resilient arm 40 furthermore acts to hold a shouldered portion 43 of the bearing member 39 against a correspondingly shouldered portion provided upon the auxiliary panel-l5. Stop pins 44 are provided adjacent to the opposite extremities ofth erow of recesses 42 for the purpose of limiting the extent to which the bearing member 39 may be moved by the operating arm 40, the pin .41 of WhlC] engages each of said stop pins. An operating knob 45 is rigidly secured to the Vernier shaft 38 by a set screw 46.

It is desirable in transmitting therota motion from thedriving member 26 tothe driven member 19 that the speed of the dial shaft 9 shall be considerably reduced, and to effect this result, the, diameter of the driving member 26 is considerably less than that of the disc 20 and friction spring 21, and the speed of the driven member 19 may be still further reduced, as compared to that of the driving member 26, by moving the bearing member 39 within the panel 15 and moving the median line of said driving member nearer to that of said driven member,-at which time the driving member 26 will engage the disc 20 and spring 21 approximately as illustrated in Fig. 5, thereby changing the effective ratio between said driving and driven members.

In tuning the radio apparatus, the rotor plates 8 of the condenser 5 are adjusted relatively to the stator plates 10 by rotating th e operating knob 45, and the rotary motion from said knob is transmitted through the driving member 26 to the driven member 19, the latter travellingat a greatly reduced speed from the speed of the operating knob 45.

If the operating arm 40 of the bearing member 39 is positioned with. the pin 41 45 to the dial shaft 9 throng thereof located within the left-hand recess 42 of the. auxiliary panel 15,the relative positions of the driving member 26 and driven member 19 will be as illustrated in Fi 3, at which time the effective ratio of the rivin member to the driven member is approx1- mately seven to one.

If, however, the operating arm 40 is moved to locate the pin 41 within the right-hand recess 42, the relative positions of the driving and driven members will be as illustrated in Fig. 5, at which time the effective ratio between said driving and driven members will be approximately eighteen to one.

It will be observed that in transmitting the rotary motion from the o eratin knob ii the riving member 26 and friction disc 20 and friction spring 21, that there will be absolutely no backlash pr %ost motipln1 and saild disc and sprin wil a we 5 tig t gri t e o osite bevele d faces of s aid drix ing iiiemberP While I have illustrated and described a preferred embodiment of my invention, I do not wish to be limited there y, my invention being best defined in the following claims.

I claim:

1. A radio apparatus having, in combination, a panel, a caring member mounted to rotate in said panel, a driving member rotatably mounted in said bearing member, a driven member embodying therein a pair of friction members engaging the opposite sides o' said driving member, an indicator fast to said driven member, said bearing member being adapted to move said driving member '3 between said friction members to change the position ofits point of contact therewith, whereb the effective ratio between said driving an driven members is varied.

2. A radio apparatus having, in combination, a panel, a bearing member mounted to rotate in said panel, a .driving member rotatably mounted in said bearing member, a driven member embodying therein a pair of friction members engaging the opposite sides of said driving member, an indicator fast to said driven member, said bearing member being adapted to move said driving member between said friction member to change the position of its pointof contact therewith, whereb the effective ratio between said driving an driven members is varied, and means to lock said bearing member in different r0 tative positions upon said panel.

3. A dial mechanism for a radio apparatus comprising in combination, a main shaft, a disc fast to said shaft, a dial rotatable with said disc, a Vernier shaft, a driving member upon said Vernier shaft engaging said disc, a spring engaging said drivin member and pressing the latter against said disc to form a frictional driving contact therewith, a bearing for said Vernier shaft having its axis eccentric to the axis of said Vernier Ill mamas comprising, in combination, a panel, a main shaft rot-stably mounted in said panel, a disc fast to said shaft, a dial fast to said disc, a

I Vernier shaft, a driving member upon said llti Vernier shaft engaging said disc, a spring engaging said driving member and pressing the latter against said disc to form a frictional driving contact therewith, a bearing member for said Vernier shaft mounted to rotate in said panel and having an axis eccentric to the axis of said vernier shaft, means for rotating said bearing member to move said vernier shaft toward or away from said main shaft, whereby the contact relation between said disc and driving mem-' her is varied to effect different driving ratios between said shafts, and means to lock said bearing member in different rotative positions upon said panel.

5. A radio apparatus having, in combination, a driven member embodying therein a rotary friction disc, a friction spring fast to said disc, an indicator of sheet material fast to a face of said disc, a driving member engaging the adjacent faces of said disc and spring and adapted to impart a rotary motion thereto, and means to move said driving member to change the position of its pomt of contact with said disc and spring, whereby the effective ratio between said driving member and driven member is varied.

6. A radio apparatus having, in combination, a panel, a friction disc rotatably mounted upon said panel, an indicator fast to said disc, a movable bearing member on said panel, a friction member mounted on said bearing eccentric to the axis thereof, a face of said friction member engaging aface of said disc, a friction spring fast to said disc and engaging another face of said friction member, whereby a rotary motion may be imparted to said indicator by the rotation of said friction member, said bearing member being adapted to move said friction member to change the position of its point of contact with said disc and spring, whereby the effective ratio between said friction member and disc and spring is varied.

'4'. A radio apparatus having, in combination, a panel, a friction disc rotatably mounted upon said panel, an indicator fast to said disc, a movable. bearing member on said panel, a friction member mounted on said bearing eccentric to the axis thereof, a face of said friction member engaging a face of said disc, a friction spring fast to said disc and engaging another face of said fric tion member, whereby a rotary motion may be imparted to saiddndicator by the rotation of said friction member, said bearing member being adapted to move said friction member to change the position of its point of contact with said disc and spring, whereby the effective ratio between said friction member and disc and spring is varied, and means to lock said bearing in difi'erent rotative positions on said panel.

8. A radio apparatus having, in combination, a panel, a friction disc rotatably mounted upon said panel, said disc being beveled upon a face thereof adj acent to the periphery thereof, a dial fast to said disc, a bearing member mounted on said panel, a friction member mounted in said bearing member eccentric to the axis thereof and provided with a beveled surface engaging the beveled surface of said disc, a friction spring fast to said disc and engaging an; other face of said friction member, whereby a rotary motion maybe imparted to said indicator by the rotation of said friction member, said bearing member being adapted to move said friction member to change the position of its point of contact with said disc and spring, whereby the effective ratio between said friction member and disc and spring is varied.

In testimony whereof I have hereunto set no hand.

y WILLIAM A. READY. 

